蛋白激酶B/雷帕霉素靶蛋白通路在七氟醚后处理保护心肌缺血再灌注中的作用  

Effect of Sevoflurane Post-conditioning on AKT/mTOR Pathway for Protecting Cardiac Ischemia/reperfusion Injury in Isolated Rat's Heart

作　　者：张静[1] 余鹏[2] 袁林辉[1] 陈勇[1] 朱晓红[1] 张列亮 周斌[1] 周志东[1] ZHANG Jing YU Peng YUAN Lin-hui CHEN Yong ZHU Xiao-hong ZHANG Lie-liang ZHOU Bin ZHOU Zhi-dong(Department of Anesthesiology, Second Affiliated Hospital of Nanchang University, Nanchang （330000）, Jiangxi, Chin)

机构地区：[1]南昌大学第二附属医院麻醉科,江西省南昌市330000 [2]南昌大学第二附属医院心内科,江西省南昌市330000

出　　处：《中国循环杂志》2016年第9期896-901,共6页Chinese Circulation Journal

摘　　要：目的:探讨七氟醚后处理对离体大鼠心肌缺血再灌注损伤的影响及蛋白激酶B(AKT)/雷帕霉素靶蛋白(m TOR)通路在其中的作用。方法:取Langendorff离体灌注模型成功的大鼠心脏84个,随机分为7组(n=12):假手术组(Sham组)、缺血再灌注组(I/R组)、七氟醚后处理组(SPC组)、NVP-BEZ235溶剂二甲基亚砜组(DMSO组)、磷脂酰肌醇-3-激酶(PI3K)/m TOR双重抑制剂NVP-BEZ235组(BEZ组)、NVP-BEZ235+七氟醚后处理组(BEZ+SPC组)和单纯七氟醚给药组(SEVO组)。除Sham组和SEVO组,其余各组缺血30 min,再灌注120 min。SPC组、DMSO组和BEZ组分别于缺血末至再灌注初15 min给予经2.4%七氟醚、DMSO(<0.2%)和NVP-BEZ235(20μmol/L)饱和的K-H液灌注,随后更换为正常K-H液再灌注105 min。BEZ+SPC组于缺血末至再灌注初15 min给予经2.4%七氟醚和NVP-BEZ235(20μmol/L)饱和的K-H液灌注。再灌注末观察各组心肌梗死范围,心肌组织病理学变化,检测蛋白[磷酸化AKT(phospho-AKT)/总的AKT(total-AKT)、磷酸化m TOR(phospho-m TOR)/总的m TOR(total-m TOR)、自噬相关基因6(Beclin1)、B淋巴细胞瘤-2(Bcl-2)相关X蛋白(Bax)/Bcl-2和活化半胱氨酸天冬氨酸蛋白酶-3(cleaved Caspase-3)]表达水平。结果:与I/R组比较,SPC组心肌梗死范围减少[(26.28±4.00)%vs(49.22±3.66)%],心肌病理损伤减轻,phosphoAKT/total-AKT和phospho-m TOR/total-m TOR表达分别上调79.85%和67.02%,Beclin1、Bax/Bcl-2和cleaved Caspase-3表达分别下调33.77%、69.26%和48.84%(P均<0.05);与SPC组比较,BEZ+SPC组心肌梗死范围增加[(53.85±4.06)%vs(26.28±4.00)%],心肌病理损伤加重,phospho-AKT/total-AKT和phospho-m TOR/total-m TOR表达分别下调46.06%和42.95%,Beclin1、Bax/Bcl-2和cleaved Caspase-3表达分别上调29.90%、206.85%和114.65%(P均<0.05)。结论:七氟醚后处理可通过激活AKT/m TOR通路,抑制心肌细胞自噬和凋亡,从而减轻离体大鼠心肌缺血再灌注损伤。Objective： To investigate the effect of sevolfurane （SEVO） post-conditioning on protein kinase B （AKT）/mammalian target of rapamycin （mTOR） pathway for protecting ischemia/reperfusion （I/R） injury in isolated rat’s heart. Methods： A total of 84 isolated rat’s heart prepared by Langendorff method were randomly divided into 7 groups andn=12 in each group.①Sham group,②I/R group,③SEVO post- conditioning （SPC） group,④NVP-BEZ235 solvent dimenthyl sulfoxide （DMSO） group,⑤Phosphatidyl inositol 3-kinase （PI3K）/mTOR dual inhibitor NVP-BEZ235 （BEZ） group,⑥BEZ＋SPC group and⑦SEVO alone group. The hearts received 30 min ischemia followed by 120 min reperfusion with relevant treatment except for Sham group and SEVO group in which the hearts were without ischemia process. Myocardial infarct （MI） size and tissue pathological changes were observed, protein expressions of phosphor-AKT （P-AKT）/total-AKT, P-mTOR/total-mTOR, Beclin1, Bax/Bcl-2 and＆amp;nbsp;cleaved Caspase-3 were examined at the end of reperfusion respectively. Results： Compared with I/R group, SPC group presented decreased MI size （26.28＆#177;4.00） % vs （49.22＆#177;3.66） % and reduced tissue pathological changes; up-regulated protein expressions of P-AKT/total-AKT and P-mTOR/total-mTOR by 79.85% and 67.02%, while down-regulated protein expressions of Beclin1, Bax/Bcl-2 and cleaved Caspase-3 by 33.77%, 69.26% and 48.84%respectively, allP〈0.05. Compared with SPC group, BEZ＋SPC group sowed increased MI size （53.85＆#177;4.06） % vs （26.28＆#177;4.00） %and elevated tissue pathological changes; down-regulated proteins expressions of P-AKT/total-AKT and P-mTOR/total-mTOR by 46.06% and 42.95%, while up-regulated protein expressions of Beclin1, Bax/Bcl-2 and cleaved Caspase-3 by 29.90%, 206.85% and 114.65% respectively, allP〈0.05. Conclusion： SPC may activate AKT/mTOR pathway and inhibit cardiomyocyte autophagy and apoptosis, thereby attenuate I/R injury in isolated rats’ heart.

关 键 词：心肌缺血再灌注损伤 雷帕霉素靶蛋白 七氟醚 

分 类 号：R54[医药卫生—心血管疾病]